Function ExplainOpenSetAsideGroup

src/backend/commands/explain.c:5746–5773

* Open a group of related objects, without emitting actual data. * * Prepare the formatting state as though we were beginning a group with * the identified properties, but don't actually emit anything. Output * subsequent to this call can be redirected into a separate output buffer, * and then eventually appended to the main output buffer after doing a * regular ExplainOpenGroup call (with

 * pop this state with ExplainSaveGroup.
 */
static void
ExplainOpenSetAsideGroup(const char *objtype, const char *labelname,
						 bool labeled, int depth, ExplainState *es)
{
	switch (es->format)
	{
		case EXPLAIN_FORMAT_TEXT:
			/* nothing to do */
			break;

		case EXPLAIN_FORMAT_XML:
			es->indent += depth;
			break;

		case EXPLAIN_FORMAT_JSON:
			es->grouping_stack = lcons_int(0, es->grouping_stack);
			es->indent += depth;
			break;

		case EXPLAIN_FORMAT_YAML:
			if (labelname)
				es->grouping_stack = lcons_int(1, es->grouping_stack);
			else
				es->grouping_stack = lcons_int(0, es->grouping_stack);
			es->indent += depth;
			break;
	}
}

/*
 * Pop one level of grouping state, allowing for a re-push later.